Master Officer Gerald Morris wrote in his report Guo was swimming at the Roanoke Rapids Lake Park with a friend around 1:30 p.m. Wednesday.
It appeared they swam 5 or 6 feet past the designated buoy and for reasons undetermined Guo began to panic and went under water.
Witnesses called 911 and rescue efforts began immediately. The boy, who was located in a dense bed of hydrilla, was recovered just after 3 p.m.
An autopsy is pending.
Deputy Chief Andy Jackson declined comment on the report this morning.